The Nutrition Labeling and Education Act of 1990 required that all food manufacturers use a standard nutritional facts label. The law went into effect in 1994, and since then, those labels have stayed pretty much the same. The only significant change came in 2006, when trans fat was added under saturated fat. Today, Michelle Obama will announce an overhaul of that familiar nutritional label, and many of the changes reflect the way our understanding of health has evolved since 1990.

Here’s what you need to know about the changes to the label, which will take effect in two years.

Added sugar: This is the most significant change. The new labels will still list grams of total sugar, but they will also now break out the amount of added sugar, along with the percentage of the Recommended Dietary Allowance of added sugar. (The RDA for added sugar in a 2,000 calorie diet is 12 teaspoons.) That means, for instance, that 20 ounces of Coca-Cola would likely be labeled as containing 130% of your RDA of added sugar for the day. Total sugar includes the sugar that is naturally occurring in the food; added sugar is the amount of sweetener that was added.

This change was fought vociferously by beverage and baked good industry groups who claim that there’s no meaningful difference between the sugar that’s naturally occurring in foods and the sugar that’s added. It’s true that there’s no chemical difference between the sugar that’s naturally occurring in grains, for instance, and the sugar that’s added, say, to Gatorade. But the FDA says that Americans currently get 16% of their total calories from added sugars, mostly from sources like soda, energy, sports and juice drinks, baked goods, and candy. The regulators argued that foods with lots of added sugars often have low nutritional value, and groups like the American Heart Association, the American Academy of Pediatrics, and the World Health Organization recommend that people cut their intake of added sugar. These new nutritional labels will make it easier for consumers to identify which products they should avoid.

Calories are easier to read; serving sizes are more realistic: Up top, you’ll notice right away that the number of calories per serving is in a larger, bolder font that’s easier to read. And the serving sizes have been adjusted from “ideal” size to a more realistic amount: One serving of ice cream will increase from 1/2 cup to 3/4 cup, for instance, and the calories and fat per serving will bump up correspondingly. Similarly, the serving size for sodas will increase from 8 ounces to 12 ounces.

Removing calories from fat: Calories derived from fat will no longer be listed because current research suggests that the type of fat you consume is more important than the total amount of fat you consume. For instance, an avocado gets about 80% of its calories from fat. But that information isn’t very meaningful because the kind of fat that avocados contain is now understood to be healthful.

Vitamin D and potassium counts are mandated: Some vitamin and mineral counts are required to be listed on labels and some are optional. Vitamin D and potassium will no longer be optional because Americans tend to not get enough of them. Vitamins A and C are switching from required to optional because Americans do tend to get enough of them.